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788 commits

Author SHA1 Message Date
Stefan Richter
9f426173e5 firewire: ohci: skip soft reset retries after card ejection
The software reset in firewire-ohci's pci_remove does not have a great
prospect of success if the card was already physically removed at this
point.  So let's skip the 500 ms that were spent in retries here.

Also, replace a defined constant by its open-coded value.  This is not a
constant from a specification but an arbitrarily chosen retry limit.  It
was only used in this single place.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-07-09 17:12:09 +02:00
Stefan Richter
215fa444c2 firewire: ohci: fix PHY reg access after card ejection
Detect and handle ejection of FireWire CardBus cards in PHY register
accesses:

  - The last attempt of firewire-core to reset the bus during shutdown
    caused a spurious "firewire_ohci: failed to write phy reg" error
    message in the log.  Skip this message as well as the prior retry
    loop that needlessly took 100 milliseconds.

  - In the unlikely case that a PHY register was read right after card
    ejection, a bogus value was obtained and possibly acted upon.
    Instead, fail the read attempt.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-07-09 17:12:08 +02:00
Stefan Richter
b14c369d87 firewire: ohci: add a comment on PHY reg access serialization
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-07-09 17:12:08 +02:00
Stefan Richter
9ef28ccd59 firewire: ohci: reduce potential context_stop latency
Stopping an isochronous reception DMA context takes two loop iterations
in context_stop on several controllers (JMicron, NEC, VIA).  But there
is no extra delay necessary between these two reg_read trials; the MMIO
reads themselves are slow enough.  Hence bring back the behavior from
before commit dd6254e5c0 "firewire: ohci:
remove superfluous posted write flushes" on these controllers by means
of an "if (i)" condition.

Isochronous context stop is performed in preemptible contexts (and only
rarely), hence this change is of little impact.  (Besides, Agere and TI
controllers always, or almost always, have the context stopped already
at the first ContextControl read.)

More important is asynchronous transmit context stop, which is performed
while local interrupts are disabled (on the two AT DMAs in
bus_reset_tasklet, i.e. after a self-ID-complete event).  In my
experience with several controllers, tested with a usermode AT-request
transmitter as well as with FTP transmission over firewire-net, the AT
contexts were luckily already stopped at the first ContextControl read,
i.e. never required another MMIO read let alone mdelay.  A possible
explanation for this is that the controllers which I tested perhaps stop
AT DMA before they perform the self-ID reception DMA.

But we cannot be sure about that and should keep the interrupts-disabled
busy loop as short as possible.  Hence, query the ContextControl
register in 1000 udelay(10) intervals instead of 10 udelay(1000)
intervals.  I understand from an estimation by Clemens Ladisch that
stopping a busy DMA context should take microseconds or at worst tens of
microseconds, not milliseconds.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-07-09 17:12:07 +02:00
Clemens Ladisch
dd6254e5c0 firewire: ohci: remove superfluous posted write flushes
The call to flush_writes() in context_stop() is superfluous because
another register read is done immediately afterwards.

The call to flush_writes() in ar_context_run() does not need to be done
individually for each AR context, so move it to ohci_enable().  This
also makes ohci_enable() clearer because it no longer depends on a side
effect of ar_context_run() to flush its own register writes.

Finally, the setting of a context's wake bit does not need to be flushed
because neither the driver logic nor the API require the CPU to wait for
this action.  This removes the last MMIO reads from the packet queueing
code paths.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-06-02 13:58:33 +02:00
August Lilleaas
bf337b15c2 firewire: net: replacing deprecated __attribute__((packed)) with __packed
Fixing a deprecation, replacing __attribute__((packed)) with __packed.
It was deprecated for portability, specifically to avoid GCC specific
code.  See commit 82ddcb0405.

Signed-off-by: August Lilleaas <august@augustl.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (added include compiler.h)
2011-06-02 13:58:33 +02:00
Stefan Richter
105e53f863 firewire: sbp2: parallelize login, reconnect, logout
The struct sbp2_logical_unit.work items can all be executed in parallel
but are not reentrant.  Furthermore, reconnect or re-login work must be
executed in a WQ_MEM_RECLAIM workqueue.

Hence replace the old single-threaded firewire-sbp2 workqueue by a
concurrency-managed but non-reentrant workqueue with rescuer.
firewire-core already maintains one, hence use this one.

In earlier versions of this change, I observed occasional failures of
parallel INQUIRY to an Initio INIC-2430 FireWire 800 to dual IDE bridge.
More testing indicates that parallel INQUIRY is not actually a problem,
but too quick successions of logout and login + INQUIRY, e.g. a quick
sequence of cable plugout and plugin, can result in failed INQUIRY.
This does not seem to be something that should or could be addressed by
serialization.

Another dual-LU device to which I currently have access to, an
OXUF924DSB FireWire 800 to dual SATA bridge with firmware from MacPower,
has been successfully tested with this too.

This change is beneficial to environments with two or more FireWire
storage devices, especially if they are located on the same bus.
Management tasks that should be performed as soon and as quickly as
possible, especially reconnect, are no longer held up by tasks on other
devices that may take a long time, especially login with INQUIRY and sd
or sr driver probe.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-05-10 22:53:46 +02:00
Stefan Richter
81bf52d862 firewire: sbp2: octlet AT payloads can be stack-allocated
We do not need slab allocations for ORB pointer write transactions
anymore in order to satisfy streaming DMA mapping constraints, thanks to
commit da28947e7e "firewire: ohci: avoid separate DMA mapping for
small AT payloads".

(Besides, the slab-allocated buffers that firewire-sbp2 used to provide
for 8-byte write requests were still not fully portable since they
shared a cacheline with unrelated CPU-accessed data.)

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-05-10 22:53:46 +02:00
Stefan Richter
b75ca5ea8e firewire: sbp2: omit Scsi_Host lock from queuecommand
firewire-sbp2 already takes care for internal serialization where
required (ORB list accesses), and it does not use cmd->serial_number
internally.  Hence it is safe to not grab the shost lock around
queuecommand.

While we are at housekeeping, drop a redundant struct member:
sbp2_command_orb.done is set once in a hot path and dereferenced once in
a hot path.  We can as well dereference sbp2_command_orb.cmd->scsi_done
instead.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-05-10 22:53:45 +02:00
Stefan Richter
6ea9e7bbfc firewire: core: use non-reentrant workqueue with rescuer
firewire-core manages the following types of work items:

fw_card.br_work:
  - resets the bus on a card and possibly sends a PHY packet before that
  - does not sleep for long or not at all
  - is scheduled via fw_schedule_bus_reset() by
      - firewire-ohci's pci_probe method
      - firewire-ohci's set_config_rom method, called by kernelspace
        protocol drivers and userspace drivers which add/remove
	Configuration ROM descriptors
      - userspace drivers which use the bus reset ioctl
      - itself if the last reset happened less than 2 seconds ago

fw_card.bm_work:
  - performs bus management duties
  - usually does not (but may in corner cases) sleep for long
  - is scheduled via fw_schedule_bm_work() by
      - firewire-ohci's self-ID-complete IRQ handler tasklet
      - firewire-core's fw_device.work instances whenever the root node
        device was (successfully or unsuccessfully) discovered,
	refreshed, or rediscovered
      - itself in case of resource allocation failures or in order to
        obey the 125ms bus manager arbitration interval

fw_device.work:
  - performs node probe, update, shutdown, revival, removal; including
    kernel driver probe, update, shutdown and bus reset notification to
    userspace drivers
  - usually sleeps moderately long, in corner cases very long
  - is scheduled by
      - firewire-ohci's self-ID-complete IRQ handler tasklet via the
        core's fw_node_event
      - firewire-ohci's pci_remove method via core's fw_destroy_nodes/
        fw_node_event
      - itself during retries, e.g. while a node is powering up

iso_resource.work:
  - accesses registers at the Isochronous Resource Manager node
  - usually does not (but may in corner cases) sleep for long
  - is scheduled via schedule_iso_resource() by
      - the owning userspace driver at addition and removal of the
        resource
      - firewire-core's fw_device.work instances after bus reset
      - itself in case of resource allocation if necessary to obey the
        1000ms reallocation period after bus reset

fw_card.br_work instances should not, and instances of the others must
not, be executed in parallel by multiple CPUs -- but were not protected
against that.  Hence allocate a non-reentrant workqueue for them.

fw_device.work may be used in the memory reclaim path in case of SBP-2
device updates.  Hence we need a workqueue with rescuer and cannot use
system_nrt_wq.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Reviewed-by: Tejun Heo <tj@kernel.org>
2011-05-10 22:53:45 +02:00
Clemens Ladisch
13882a82ee firewire: optimize iso queueing by setting wake only after the last packet
When queueing iso packets, the run time is dominated by the two
MMIO accesses that set the DMA context's wake bit.  Because most
drivers submit packets in batches, we can save much time by
removing all but the last wakeup.

The internal kernel API is changed to require a call to
fw_iso_context_queue_flush() after a batch of queued packets.
The user space API does not change, so one call to
FW_CDEV_IOC_QUEUE_ISO must specify multiple packets to take
advantage of this optimization.

In my measurements, this patch reduces the time needed to queue
fifty skip packets from userspace to one sixth on a 2.5 GHz CPU,
or to one third at 800 MHz.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-05-10 22:53:45 +02:00
Stefan Richter
f30e6d3e41 firewire: octlet AT payloads can be stack-allocated
We do not need slab allocations anymore in order to satisfy
streaming DMA mapping constraints, thanks to commit da28947e7e
"firewire: ohci: avoid separate DMA mapping for small AT payloads".

(Besides, the slab-allocated buffers that firewire-core, firewire-sbp2,
and firedtv used to provide for 8-byte write and lock requests were
still not fully portable since they crossed cacheline boundaries or
shared a cacheline with unrelated CPU-accessed data.  snd-firewire-lib
got this aspect right by using an extra kmalloc/ kfree just for the
8-byte transaction buffer.)

This change replaces kmalloc'ed lock transaction scratch buffers in
firewire-core, firedtv, and snd-firewire-lib by local stack allocations.
Perhaps the most notable result of the change is simpler locking because
there is no need to serialize usages of preallocated per-device buffers
anymore.  Also, allocations and deallocations are simpler.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Acked-by: Clemens Ladisch <clemens@ladisch.de>
2011-05-10 22:53:44 +02:00
Stefan Richter
020abf03cd Merge tag 'v2.6.39-rc7'
in order to pull in changes in drivers/media/dvb/firewire/ and
sound/firewire/.
2011-05-10 22:50:41 +02:00
Linus Torvalds
8db72a7d72 Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
  firewire: Fix for broken configrom updates in quick succession
2011-05-04 14:21:39 -07:00
B.J. Buchalter
2e053a27d9 firewire: Fix for broken configrom updates in quick succession
Current implementation of ohci_set_config_rom() uses a deferred
bus reset via fw_schedule_bus_reset(). If clients add multiple
unit descriptors to the config_rom in quick succession, the
deferred bus reset may not have fired before succeeding update
requests have come in. This can lead to an incorrect partial
update of the config_rom for both addition and removal of
config_rom descriptors, as the ohci_set_config_rom() routine
will return -EBUSY if a previous pending update has not been
completed yet; the requested update just gets dropped on the floor.

This patch recognizes that the "in-flight" update can be modified
until it has been processed by the bus-reset, and the locking
in the bus_reset_tasklet ensures that the update is done atomically
with respect to modifications made by ohci_set_config_rom(). The
-EBUSY error case is simply removed.

[Stefan R:  The bug always existed at least theoretically.  But it
became easy to trigger since 2.6.36 commit 02d37bed18 "firewire: core:
integrate software-forced bus resets with bus management" which
introduced long mandatory delays between janitorial bus resets.]

Signed-off-by: Benjamin Buchalter <bj@mhlabs.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (trivial style changes)
Cc: <stable@kernel.org> # 2.6.36.y and newer
2011-05-02 22:55:22 +02:00
Clemens Ladisch
0ff8fbc617 firewire: ohci: optimize find_branch_descriptor()
When z==2, the condition "key == 2" is superfluous because it cannot
occur without "b == 3", as a descriptor with b!=3 and key==2 would be
an OUTPUT_MORE_IMMEDIATE descriptor which cannot be used alone.

Also remove magic numbers and needless computations on the b field.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-04-19 20:00:11 +02:00
Clemens Ladisch
da28947e7e firewire: ohci: avoid separate DMA mapping for small AT payloads
For AT packet payloads of up to eight bytes, we have enough unused space
in the DMA descriptors list so that we can put a copy of the payload
there and thus avoid having to create a separate streaming DMA mapping
for the payload buffer.

In a CPU-bound microbenchmark that just sends 8-byte packets, bandwidth
was measured to increase by 5.7 %, from 1009 KB/s to 1067 KB/s.  In
practice, the only performance-sensitive usage of small asynchronous
packets is the SBP-2 driver's write to the ORB_POINTER register during
SCSI command submission.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-04-19 20:00:11 +02:00
Clemens Ladisch
ecf8328e59 firewire: ohci: do not start DMA contexts before link is enabled
OHCI 1.1 5.7.3 not only forbids enabling or starting any DMA contexts
before the linkEnable bit is set, but also explicitly warns of undefined
behaviour if this order is violated.

Don't violate it then.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-04-19 20:00:10 +02:00
Lucas De Marchi
25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Linus Torvalds
c3ca48f062 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
  firewire: core: ignore link-active bit of new nodes, fix device recognition
  firewire: sbp2: revert obsolete 'fix stall with "Unsolicited response"'
  firewire: core: increase default SPLIT_TIMEOUT value
  firewire: ohci: Misleading kfree in ohci.c::pci_probe/remove
  firewire: ohci: omit IntEvent.busReset check rom AT queueing
  firewire: ohci: prevent starting of iso contexts with empty queue
  firewire: ohci: prevent iso completion callbacks after context stop
  firewire: core: rename some variables
  firewire: nosy: should work on Power Mac G4 PCI too
  firewire: core: fix card->reset_jiffies overflow
  firewire: cdev: remove unneeded reference
  firewire: cdev: always wait for outbound transactions to complete
  firewire: cdev: remove unneeded idr_find() from complete_transaction()
  firewire: ohci: log dead DMA contexts
2011-03-21 10:05:22 -07:00
Stefan Richter
115881d395 firewire: core: ignore link-active bit of new nodes, fix device recognition
Like the older ieee1394 core driver, firewire-core skipped scanning of
any new node whose PHY sent a self ID without "link active" bit.  If a
device had this bit off mistakenly, it meant that it was inaccessible to
kernel drivers with the old IEEE 1394 driver stack but could still be
accessed by userspace drivers through the raw1394 interface.

But with firewire-core, userspace drivers don't get to see such buggy
devices anymore.  This is effectively a driver regression since this
device bug is otherwise harmless.

We now attempt to scan all devices, even repeaters that don't have a
link or powered-down devices that have everything but their PHY shut
down when plugged in.  This results in futile repeated scanning attempts
in case of such devices that really don't have an active link, but this
doesn't hurt since recent workqueue infrastructure lets us run more
concurrent scanning jobs than we can shake a stick at.

This should fix accessibility of Focusrite Saffire PRO 26 I/O:
http://sourceforge.net/mailarchive/forum.php?thread_name=20110314215622.5c751bb0%40stein&forum_name=ffado-user

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-03-20 16:45:25 +01:00
Stefan Richter
7a4e1e9c68 firewire: sbp2: revert obsolete 'fix stall with "Unsolicited response"'
Now that firewire-core sets the local node's SPLIT_TIMEOUT to 2 seconds
per default, commit a481e97d3c is no
longer required.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-03-20 16:45:24 +01:00
Clemens Ladisch
dd5eeb99f4 firewire: core: increase default SPLIT_TIMEOUT value
The SPLIT_TIMEOUT mechanism is intended to detect requests that somehow
got lost.  However, when the timeout value is too low, transactions that
could have been completed successfully will be cancelled.  Furthermore,
there are chips whose firmwares ignore the configured split timeout and
send late split response; known examples are the DM1x00 (BeBoB), TCD22x0
(DICE), and some OXUF936QSE firmwares.

This patch changes the default timeout to two seconds, which happens to
be the default on other OSes, too.

Actual lost requests are extremely rare, so there should be no practical
downside to increasing the split timeout even on devices that work
correctly.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-03-20 16:45:24 +01:00
Clemens Ladisch
31ef9134eb ALSA: add LaCie FireWire Speakers/Griffin FireWave Surround driver
Add a driver for two playback-only FireWire devices based on the OXFW970
chip.

v2: better AMDTP API abstraction; fix fw_unit leak; small fixes
v3: cache the iPCR value
v4: FireWave constraints; fix fw_device reference counting;
    fix PCR caching; small changes and fixes
v5: volume/mute support; fix crashing due to pcm stop races
v6: fix build; one-channel volume for LaCie
v7: use signed values to make volume (range checks) work; fix function
    block IDs for volume/mute; always use channel 0 for LaCie volume

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Acked-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Tested-by: Jay Fenlason <fenlason@redhat.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2011-03-15 08:42:22 +01:00
Oleg Drokin
d838d2c09a firewire: ohci: Misleading kfree in ohci.c::pci_probe/remove
It seems drivers/firewire/ohci.c is making some optimistic assumptions
about struct fw_ohci and that member "card" will always remain the first
member of the struct.
Plus it's probably going to confuse a lot of static code analyzers too.

So I wonder if there is a good reason not to free the ohci struct just
like it was allocated instead of the tricky &ohci->card way?

Signed-off-by: Oleg Drokin <green@linuxhacker.ru>

It is perhaps just a rudiment from before mainline submission of the
driver.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-03-14 23:30:57 +01:00
Stefan Richter
b6258fc1fe firewire: ohci: omit IntEvent.busReset check rom AT queueing
Since commit 82b662dc41 "flush AT contexts after bus reset for OHCI 1.2",
the driver takes care of any AT packets that were enqueued during a bus
reset phase.  The check from commit 76f73ca1b2 is therefore no longer
necessary and the MMIO read can be avoided.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-03-14 23:30:56 +01:00
Clemens Ladisch
44b74d909d firewire: ohci: prevent starting of iso contexts with empty queue
If a misguided program tried to start an isochronous context before it
has queued any packets, the call would appear to succeed, but the
context would not actually go into the running state, and the OHCI
controller would then raise an unrecoverableError interrupt because the
first Z value is zero and thus invalid.  The driver logs such errors,
but there is no mechanism to report this back to the program.

Add an explicit check so that this error can be returned synchronously.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-02-26 15:11:04 +01:00
Clemens Ladisch
e81cbebdfc firewire: ohci: prevent iso completion callbacks after context stop
To prevent the iso packet callback from being called after
fw_iso_context_stop() has returned, make sure that the
context's tasklet has finished executing before that.

This fixes access-after-free bugs that have so far been
observed only in the upcoming snd-firewire-speakers driver,
but can theoretically also happen in the firedtv driver.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-02-26 15:11:03 +01:00
Clemens Ladisch
5aaffc65a2 firewire: core: rename some variables
In manage_channel(), rename the variables "c" and "i" to the more
expressive "bit" and "channel".

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-02-26 15:11:03 +01:00
Stefan Richter
8fd2af11d2 firewire: nosy: should work on Power Mac G4 PCI too
The first board generation of Power Mac G4 ("Yikes!", those with PCI
graphics) still had a PCILynx controller like their G3 predecessors,
but not the later AGP models.  (Jonathan Woithe recalls to have heard
of it, and some web sources reinforce it.)

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-02-26 15:11:03 +01:00
Clemens Ladisch
e71084af58 firewire: core: fix card->reset_jiffies overflow
On a 32-bit machine with, e.g., HZ=1000, jiffies will overflow after
about 50 days, so if there are between 25 and 50 days between bus
resets, the card->reset_jiffies comparisons can get wrong results.

To fix this, ensure that this timestamp always uses 64 bits.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: "Stefan Richter" <stefanr@s5r6.in-berlin.de>
2011-01-23 12:31:01 +01:00
Clemens Ladisch
dbc9880fa7 firewire: cdev: remove unneeded reference
For outbound transactions, the IDR's and the callback's references now
have exactly the same lifetime, so we do not need both of them.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: "Stefan Richter" <stefanr@s5r6.in-berlin.de>
2011-01-23 12:31:01 +01:00
Clemens Ladisch
5a5e62da9b firewire: cdev: always wait for outbound transactions to complete
We must not use fw_cancel_transaction() because it cannot correctly
abort still-active transactions.  The only place in core-cdev where this
matters is when the file is released.  Instead of trying to abort the
transactions, we wait for them to complete normally, i.e., until all
outbound transaction resources have been removed from the IDR tree.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: "Stefan Richter" <stefanr@s5r6.in-berlin.de>
2011-01-23 12:31:00 +01:00
Clemens Ladisch
3e204dfcaf firewire: cdev: remove unneeded idr_find() from complete_transaction()
Outbound transactions are never aborted with release_client_resource(),
so it is not necessary for complete_transaction() to check whether the
resource is still registered.  Only shutdown_resource() can abort such
an transaction, and this is already handled with the in_shutdown check.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: "Stefan Richter" <stefanr@s5r6.in-berlin.de>
2011-01-23 12:31:00 +01:00
Clemens Ladisch
f117a3e300 firewire: ohci: log dead DMA contexts
When a DMA context goes into the dead state (and the controller thus
stops working correctly), logging this error and the controller's error
code might be helpful for debugging.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-01-23 12:31:00 +01:00
Linus Torvalds
a1d3f5b70d Merge branches 'fixes' and 'fwnet' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
  firewire: core: fix unstable I/O with Canon camcorder

* 'fwnet' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
  firewire: net: is not experimental anymore
  firewire: net: invalidate ARP entries of removed nodes
2011-01-21 13:34:39 -08:00
Stefan Richter
324719978d firewire: net: is not experimental anymore
thanks to Clemens' and Maxim's fixes to firewire-ohci and -net in the
last two kernel releases.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-01-21 00:36:00 +01:00
Maxim Levitsky
74a1450499 firewire: net: invalidate ARP entries of removed nodes
This makes it possible to resume communication with a node that dropped
off the bus for a brief period.  Otherwise communication will only be
possible after ARP cache entry timeouts.

Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (rebased)
2011-01-21 00:36:00 +01:00
Stefan Richter
6044565af4 firewire: core: fix unstable I/O with Canon camcorder
Regression since commit 1038953674, "firewire: core: check for 1394a
compliant IRM, fix inaccessibility of Sony camcorder":

The camcorder Canon MV5i generates lots of bus resets when asynchronous
requests are sent to it (e.g. Config ROM read requests or FCP Command
write requests) if the camcorder is not root node.  This causes drop-
outs in videos or makes the camcorder entirely inaccessible.
https://bugzilla.redhat.com/show_bug.cgi?id=633260

Fix this by allowing any Canon device, even if it is a pre-1394a IRM
like MV5i are, to remain root node (if it is at least Cycle Master
capable).  With the FireWire controller cards that I tested, MV5i always
becomes root node when plugged in and left to its own devices.

Reported-by: Ralf Lange
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: <stable@kernel.org> # 2.6.32.y and newer
2011-01-21 00:27:46 +01:00
Clemens Ladisch
1427130425 firewire: ohci: fix compilation on arches without PAGE_KERNEL_RO
PAGE_KERNEL_RO is not available on all architectures, so its use
in the new AR code broke compilation on sparc64.

Because the read-only mapping was just a debugging aid, just use
PAGE_KERNEL instead.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>

James Bottomley wrote:
> On Thu, 2011-01-13 at 08:27 +0100, Clemens Ladisch wrote:
>> firewire: ohci: fix compilation on arches without PAGE_KERNEL_RO, e.g. sparc
>>
>> PAGE_KERNEL_RO is not available on all architectures, so its use in the
>> new AR code broke compilation on sparc64.
>>
>> Because the R/O mapping is only used to catch drivers that try to write
>> to the reception buffer and not actually required for correct operation,
>> we can just use a normal PAGE_KERNEL mapping where _RO is not available.
[...]
>> +/*
>> + * For archs where PAGE_KERNEL_RO is not supported;
>> + * mapping the AR buffers readonly for the CPU is just a debugging aid.
>> + */
>> +#ifndef PAGE_KERNEL_RO
>> +#define PAGE_KERNEL_RO PAGE_KERNEL
>> +#endif
>
> This might cause interesting issues on sparc64 if it ever acquired a
> PAGE_KERNEL_RO.  Sparc64 has extern pgprot_t for it's PAGE_KERNEL types
> rather than #defines, so the #ifdef check wouldn't see this.
>
> I think either PAGE_PROT_RO becomes part of our arch API (so all
> architectures are forced to add it), or, if it's not part of the API,
> ohci isn't entitled to use it.  The latter seems simplest since you have
> no real use for write protection anyway.

Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-01-13 15:48:29 +01:00
Clemens Ladisch
410cf2bd3d firewire: use split transaction timeout only for split transactions
Instead of starting the split transaction timeout timer when any request
is submitted, start it only when the destination's ACK_PENDING has been
received.  This prevents us from using a timeout that is too short, and,
if the controller's AT queue is emptying very slowly, from cancelling
a packet that has not yet been sent.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-01-04 08:48:34 +01:00
Stefan Richter
693a50b511 firewire: ohci: consolidate context status flags
"firewire: ohci: restart iso DMA contexts on resume from low power mode"
added the flag struct context.active and "firewire: ohci: cache the
context run bit" added struct context.running.

These flags contain the same information; combine them.
Also, normalize whitespace in pci_resume().

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-01-04 08:48:33 +01:00
Clemens Ladisch
386a4153a2 firewire: ohci: cache the context run bit
The DMA context run control bit is entirely controlled by software, so
it is safe to cache it.  This allows the driver to avoid doing an
additional MMIO read when queueing an AT packet.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-01-04 08:48:33 +01:00
Stefan Richter
78dec56d6a firewire: ohci: flush AT contexts after bus reset - addendum
Add comments
  - on why bus_reset_tasklet flushes AT queues,
  - that commit 76f73ca1b2 can possibly be reverted now.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Acked-by: Jarod Wilson <jarod@redhat.com>
2011-01-04 08:48:33 +01:00
Clemens Ladisch
82b662dc41 firewire: ohci: flush AT contexts after bus reset for OHCI 1.2
The OHCI 1.2 (draft) specification, clause 7.2.3.3, allows and
recommends that, after a bus reset, the controller does not flush all
the packets in the AT queues.  Therefore, the driver has to do this
itself.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-01-03 22:34:48 +01:00
Stefan Richter
c16714704b firewire: net: set carrier state at ifup
At ifup, carrier status would be shown on even if it actually was off.
Also add an include for ethtool_ops rather than to rely on the one from
netdevice.h.

Note, we can alas not use fwnet_device_mutex to serialize access to
dev->peer_count (as I originally wanted).  This would cause a lock
inversion:
  - fwnet_probe | takes fwnet_device_mutex
      + register_netdev | takes rtnl_mutex
  - devinet_ioctl | takes rtnl_mutex
      + fwnet_open | ...must not take fwnet_device_mutex

Hence use the dev->lock spinlock for serialization.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-12-19 15:27:02 +01:00
Maxim Levitsky
18bb36f9fa firewire: net: add carrier detection
To make userland, e.g. NetworkManager work with firewire, we need to
detect whether cable is plugged or not.  Simple and correct way of doing
that is just counting number of peers.  No peers - no link and vice
versa.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-12-19 15:27:01 +01:00
Maxim Levitsky
c4d6fd40df firewire: net: ratelimit error messages
Unfortunately its easy to trigger such error messages by removing the
cable while sending streams of data over the link.

Such errors are normal, and therefore this patch stops firewire-net from
flooding the kernel log with these errors, by combining series of same
errors together.

Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com>

(Stefan R:)  Eventually we should remove this logging when firewire-net
and related firewire-ohci facilities have been stabilized.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-12-13 20:39:15 +01:00
Maxim Levitsky
dd23736e09 firewire: ohci: restart iso DMA contexts on resume from low power mode
Restore iso channels DMA so that iso channels could continue to work
after resume from RAM/disk.

Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-12-13 20:39:15 +01:00
Maxim Levitsky
8662b6b029 firewire: ohci: restore GUID on resume.
Some lousy BIOSes, e.g. my Aspire 5720 BIOS forget to restore the GUID
register on resume from RAM.

Fix that by setting it to the last value that was read from it.

Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-12-13 20:39:15 +01:00
Clemens Ladisch
ec766a7970 firewire: ohci: use common buffer for self IDs and AR descriptors
The buffers used for the selfIDs packets and the AR request and response
descriptors end up using three pages because dma_alloc_coherent()
allocates at least one page per call.  However, these data structures
would all fit into 4 KB, so we can save space by using a common buffer
for them.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-12-13 20:39:15 +01:00
Clemens Ladisch
2dd5bed593 firewire: ohci: optimize iso context checks in the interrupt handler
When the isochRx/isochTx bit is clear, we do not need to read the
corresponding iso interrupt event register.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-12-13 20:39:14 +01:00
Clemens Ladisch
5b06db166c firewire: make PHY packet header format consistent
Change the header of PHY packets to be sent to include a pseudo
transaction code.  This makes the header consistent with that of
received PHY packets, and allows at_context_queue_packet() and
log_ar_at_event() to see the packet type directly instead of having
to deduce it from the header length or even from the header contents.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-12-13 20:39:14 +01:00
Clemens Ladisch
8327b37b18 firewire: ohci: properly clear posted write errors
To remove the error information from the controller's queue and to allow
more posted writes, the driver has to read the failed posted write
address before clearing the postedWriteErr interrupt bit.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>

(Stefan R:) The spec is somewhat fuzzy about the actual requirements.
To err on the safe side, let's do these two read accesses.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-12-13 20:39:14 +01:00
Clemens Ladisch
e597e9898a firewire: ohci: flush MMIO writes in the interrupt handler
Make sure that interrupt event clear bit writes are executed before the
interrupt handler returns.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-12-13 20:39:14 +01:00
Clemens Ladisch
c088ab30eb firewire: ohci: fix AT context initialization error handling
Add proper error handling for the context_init() calls.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-12-13 20:39:13 +01:00
Clemens Ladisch
7a39d8b821 firewire: ohci: Asynchronous Reception rewrite
Move the AR DMA descriptors out of the buffer pages, and map the buffer
pages linearly into the kernel's address space.  This allows the driver
to ignore any page boundaries in the DMA data and thus to avoid any
copying around of packet payloads.

This fixes the bug where S800 packets that are so big (> 4080 bytes)
that they can be split over three pages were not handled correctly.

Due to the changed algorithm, we can now use arbitrarily many buffer
pages, which improves performance because the controller can more easily
unload its DMA FIFO.

Furthermore, using streaming DMA mappings should improve perfomance on
architectures where coherent DMA mappings are not cacheable.  Even on
other architectures, the caching behaviour should be improved slightly
because the CPU no longer writes to the buffer pages.

v2: Detect the last filled buffer page by searching the descriptor's
    residual count value fields in order (like in the old code), instead
    of going backwards through the transfer status fields; it looks as
    if some controllers do not set the latter correctly.

v3: Fix an old resume bug that would now make the handler run into
    a BUG_ON, and replace that check with more useful error handling.
    Increase the buffer size for better performance with non-TI chips.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>

Maxim Levitsky writes:
    Works almost perfectly.  I can still see RCODE_BUSY errors
    sometimes, not very often though.  64K here eliminates these errors
    completely.  This is most likely due to nouveau drivers and lowest
    perf level I use to lower card temperature.  That increases
    latencies too much I think.  Besides that the IO is just perfect.

Tested-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-12-13 20:39:13 +01:00
Joe Perches
5878730be4 firewire: core: Update WARN uses
Add missing newlines.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-12-12 15:47:03 +01:00
Stefan Richter
60a74a6ff8 firewire: nosy: char device is not seekable
Amend .open handler accordingly and remove the .llseek handler.
.llseek = NULL means no_llseek (return error) since commit 776c163b1b.

The only client that uses this interface is nosy-dump in linux/tools/firewire
and it knows not to seek in this char dev.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-12-12 15:47:02 +01:00
Stefan Richter
9993e0fe0f firewire: ohci: fix regression with Agere FW643 rev 06, disable MSI
Agere FW643 rev 06, listed as "11c1:5901 (rev 06) (prog-if 10 [OHCI])",
produced SBP-2 I/O errors since kernel 2.6.36.  Disabling MSI fixes it.

Since MSI work on Agere FW643-E (same vendor and device ID, but rev 07),
introduce a device revision field into firewire-ohci's quirks list so
that different quirks can be defined for older and newer revisions.

Reported-by: Jonathan Isom <jeisom@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: <stable@kernel.org> # 2.6.36.y
2010-12-12 15:47:02 +01:00
Stefan Richter
af0cdf4947 firewire: ohci: fix regression with VIA VT6315, disable MSI
"VIA Technologies, Inc. VT6315 Series Firewire Controller [1106:3403]"
does not generate any interrupts if Message Signaled Interrupts were
enabled.  This is a regression since kernel 2.6.36 in which MSI support
was added to firewire-ohci.  Hence blacklist MSI on all VIA controllers.

Reported-by: Robin Cook <rcook@wyrms.net>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: <stable@kernel.org> # 2.6.36.y
2010-12-12 15:47:02 +01:00
Linus Torvalds
75f5d2c9bd Merge branch 'fwnet' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6
* 'fwnet' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
  firewire: net: throttle TX queue before running out of tlabels
  firewire: net: replace lists by counters
  firewire: net: fix memory leaks
  firewire: net: count stats.tx_packets and stats.tx_bytes
2010-11-28 12:24:20 -08:00
Stefan Richter
b2268830f5 firewire: net: throttle TX queue before running out of tlabels
This prevents firewire-net from submitting write requests in fast
succession until failure due to all 64 transaction labels were used up
for unfinished split transactions.  The netif_stop/wake_queue API is
used for this purpose.

Without this stop/wake mechanism, datagrams were simply lost whenever
the tlabel pool was exhausted.  Plus, tlabel exhaustion by firewire-net
also prevented other unrelated outbound transactions to be initiated.

The chosen queue depth was checked by me to hit the maximum possible
throughput with an OS X peer whose receive DMA is good enough to never
reject requests due to busy inbound request FIFO.  Current Linux peers
show a mixed picture of -5%...+15% change in bandwidth; their current
bottleneck are RCODE_BUSY situations (fewer or more, depending on TX
queue depth) due to too small AR buffer in firewire-ohci.

Maxim Levitsky tested this change with similar watermarks with a Linux
peer and some pending firewire-ohci improvements that address the
RCODE_BUSY problem and confirmed that these TX queue limits are good.

Note:  This removes some netif_wake_queue from reception code paths.
They were apparently copy&paste artefacts from a nonsensical
netif_wake_queue use in the older eth1394 driver.  This belongs only
into the transmit path.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Tested-by: Maxim Levitsky <maximlevitsky@gmail.com>
2010-11-17 00:08:49 +01:00
Stefan Richter
48553011ce firewire: net: replace lists by counters
The current transmit code does not at all make use of
  - fwnet_device.packet_list
and only very limited use of
  - fwnet_device.broadcasted_list,
  - fwnet_device.queued_packets.
Their current function is to track whether the TX soft-IRQ finished
dealing with an skb when the AT-req tasklet takes over, and to discard
pending tx datagrams (if there are any) when the local node is removed.

The latter does actually contain a race condition bug with TX soft-IRQ
and AT-req tasklet.

Instead of these lists and the corresponding link in fwnet_packet_task,
  - a flag in fwnet_packet_task to track whether fwnet_tx is done,
  - a counter of queued datagrams in fwnet_device
do the job as well.

The above mentioned theoretic race condition is resolved by letting
fwnet_remove sleep until all datagrams were flushed.  It may sleep
almost arbitrarily long since fwnet_remove is executed in the context of
a multithreaded (concurrency managed) workqueue.

The type of max_payload is changed to u16 here to avoid waste in struct
fwnet_packet_task.  This value cannot exceed 4096 per IEEE 1394:2008
table 16-18 (or 32678 per specification of packet headers, if there is
ever going to be something else than beta mode).

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-11-17 00:08:48 +01:00
Stefan Richter
7ee11fa8d0 firewire: net: fix memory leaks
a) fwnet_transmit_packet_done used to poison ptask->pt_link by list_del.
If fwnet_send_packet checked later whether it was responsible to clean
up (in the border case that the TX soft IRQ was outpaced by the AT-req
tasklet on another CPU), it missed this because ptask->pt_link was no
longer shown as empty.

b) If fwnet_write_complete got an rcode other than RCODE_COMPLETE, we
missed to free the skb and ptask entirely.

Also, count stats.tx_dropped and stats.tx_errors when rcode != 0.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-11-17 00:08:48 +01:00
Stefan Richter
902bca00dc firewire: net: count stats.tx_packets and stats.tx_bytes
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-11-17 00:08:48 +01:00
Jeff Garzik
f281233d3e SCSI host lock push-down
Move the mid-layer's ->queuecommand() invocation from being locked
with the host lock to being unlocked to facilitate speeding up the
critical path for drivers who don't need this lock taken anyway.

The patch below presents a simple SCSI host lock push-down as an
equivalent transformation.  No locking or other behavior should change
with this patch.  All existing bugs and locking orders are preserved.

Additionally, add one parameter to queuecommand,
	struct Scsi_Host *
and remove one parameter from queuecommand,
	void (*done)(struct scsi_cmnd *)

Scsi_Host* is a convenient pointer that most host drivers need anyway,
and 'done' is redundant to struct scsi_cmnd->scsi_done.

Minimal code disturbance was attempted with this change.  Most drivers
needed only two one-line modifications for their host lock push-down.

Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Acked-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-16 13:33:23 -08:00
Linus Torvalds
f69fa76482 Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
  firewire: ohci: fix race when reading count in AR descriptor
  firewire: ohci: avoid reallocation of AR buffers
  firewire: ohci: fix race in AR split packet handling
  firewire: ohci: fix buffer overflow in AR split packet handling
2010-11-05 14:17:22 -07:00
Clemens Ladisch
693fa7792e firewire: ohci: fix race when reading count in AR descriptor
If the controller is storing a split packet and therefore changing
d->res_count to zero between the two reads by the driver, we end up with
an end pointer that is not at a packet boundary, and therefore overflow
the buffer when handling the split packet.

To fix this, read the field once, atomically.  The compiler usually
merges the two reads anyway, but for correctness, we have to enforce it.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Tested-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-10-30 23:37:20 +02:00
Clemens Ladisch
837596a61b firewire: ohci: avoid reallocation of AR buffers
Freeing an AR buffer page just to allocate a new page immediately
afterwards is not only a pointless effort but also dangerous because
the allocation can fail, which would result in an oops later.

Split ar_context_add_page() into two functions so that we can reuse
the old page directly.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Tested-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-10-30 23:37:20 +02:00
Clemens Ladisch
a1f805e5e7 firewire: ohci: fix race in AR split packet handling
When handling an AR buffer that has been completely filled, we assumed
that its descriptor will not be read by the controller and can be
overwritten.  However, when the last received packet happens to end at
the end of the buffer, the controller might not yet have moved on to the
next buffer and might read the branch address later.  If we overwrite
and free the page before that, the DMA context will either go dead
because of an invalid Z value, or go off into some random memory.

To fix this, ensure that the descriptor does not get overwritten by
using only the actual buffer instead of the entire page for reassembling
the split packet.  Furthermore, to avoid freeing the page too early,
move on to the next buffer only when some data in it guarantees that the
controller has moved on.

This should eliminate the remaining firewire-net problems.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Cc: 2.6.22-2.6.36 <stable@kernel.org>
Tested-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-10-30 23:37:19 +02:00
Clemens Ladisch
85f7ffd5d2 firewire: ohci: fix buffer overflow in AR split packet handling
When the controller had to split a received asynchronous packet into two
buffers, the driver tries to reassemble it by copying both parts into
the first page.  However, if size + rest > PAGE_SIZE, i.e., if the yet
unhandled packets before the split packet, the split packet itself, and
any received packets after the split packet are together larger than one
page, then the memory after the first page would get overwritten.

To fix this, do not try to copy the data of all unhandled packets at
once, but copy the possibly needed data every time when handling
a packet.

This gets rid of most of the infamous crashes and data corruptions when
using firewire-net.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Cc: 2.6.22-2.6.36 <stable@kernel.org>
Tested-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (cast PAGE_SIZE to size_t)
2010-10-30 23:37:19 +02:00
Linus Torvalds
b7d41a9fbb Merge branch 'ieee1394-removal' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6
* 'ieee1394-removal' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
  ieee1394: remove the old IEEE 1394 driver stack
  ieee1394: move init_ohci1394_dma to drivers/firewire/

Fix trivial change/delete conflict: drivers/ieee1394/eth1394.c is
getting removed, but was modified by the networking merge.
2010-10-25 08:05:29 -07:00
Linus Torvalds
5f05647dd8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1699 commits)
  bnx2/bnx2x: Unsupported Ethtool operations should return -EINVAL.
  vlan: Calling vlan_hwaccel_do_receive() is always valid.
  tproxy: use the interface primary IP address as a default value for --on-ip
  tproxy: added IPv6 support to the socket match
  cxgb3: function namespace cleanup
  tproxy: added IPv6 support to the TPROXY target
  tproxy: added IPv6 socket lookup function to nf_tproxy_core
  be2net: Changes to use only priority codes allowed by f/w
  tproxy: allow non-local binds of IPv6 sockets if IP_TRANSPARENT is enabled
  tproxy: added tproxy sockopt interface in the IPV6 layer
  tproxy: added udp6_lib_lookup function
  tproxy: added const specifiers to udp lookup functions
  tproxy: split off ipv6 defragmentation to a separate module
  l2tp: small cleanup
  nf_nat: restrict ICMP translation for embedded header
  can: mcp251x: fix generation of error frames
  can: mcp251x: fix endless loop in interrupt handler if CANINTF_MERRF is set
  can-raw: add msg_flags to distinguish local traffic
  9p: client code cleanup
  rds: make local functions/variables static
  ...

Fix up conflicts in net/core/dev.c, drivers/net/pcmcia/smc91c92_cs.c and
drivers/net/wireless/ath/ath9k/debug.c as per David
2010-10-23 11:47:02 -07:00
Linus Torvalds
092e0e7e52 Merge branch 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl
* 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl:
  vfs: make no_llseek the default
  vfs: don't use BKL in default_llseek
  llseek: automatically add .llseek fop
  libfs: use generic_file_llseek for simple_attr
  mac80211: disallow seeks in minstrel debug code
  lirc: make chardev nonseekable
  viotape: use noop_llseek
  raw: use explicit llseek file operations
  ibmasmfs: use generic_file_llseek
  spufs: use llseek in all file operations
  arm/omap: use generic_file_llseek in iommu_debug
  lkdtm: use generic_file_llseek in debugfs
  net/wireless: use generic_file_llseek in debugfs
  drm: use noop_llseek
2010-10-22 10:52:56 -07:00
David S. Miller
2198a10b50 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	net/core/dev.c
2010-10-21 08:43:05 -07:00
Stefan Richter
aa0170fff3 firewire: ohci: fix TI TSB82AA2 regression since 2.6.35
Revert commit 54672386cc
"firewire: ohci: fix up configuration of TI chips".
It caused massive slow-down and data corruption with a TSB82AA2 based
StarTech EC1394B2 ExpressCard and FireWire 800 harddisks.

https://bugs.launchpad.net/ubuntu/+source/linux/+bug/657081
http://thread.gmane.org/gmane.linux.kernel.firewire.user/4013

The fact that some card EEPROMs do not program these enhancements may be
related to TSB81BA3 phy chip errata, if not to bugs of TSB82AA2 itself.
We could re-add these configuration steps, but only conditional on a
whitelist of cards on which these enhancements bring a proven positive
effect.

Reported-and-tested-by: Eric Shattow <lucent@gmail.com>
Cc: Clemens Ladisch <clemens@ladisch.de>
Cc: <stable@kernel.org> 2.6.35
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-10-17 14:09:12 +02:00
Arnd Bergmann
6038f373a3 llseek: automatically add .llseek fop
All file_operations should get a .llseek operation so we can make
nonseekable_open the default for future file operations without a
.llseek pointer.

The three cases that we can automatically detect are no_llseek, seq_lseek
and default_llseek. For cases where we can we can automatically prove that
the file offset is always ignored, we use noop_llseek, which maintains
the current behavior of not returning an error from a seek.

New drivers should normally not use noop_llseek but instead use no_llseek
and call nonseekable_open at open time.  Existing drivers can be converted
to do the same when the maintainer knows for certain that no user code
relies on calling seek on the device file.

The generated code is often incorrectly indented and right now contains
comments that clarify for each added line why a specific variant was
chosen. In the version that gets submitted upstream, the comments will
be gone and I will manually fix the indentation, because there does not
seem to be a way to do that using coccinelle.

Some amount of new code is currently sitting in linux-next that should get
the same modifications, which I will do at the end of the merge window.

Many thanks to Julia Lawall for helping me learn to write a semantic
patch that does all this.

===== begin semantic patch =====
// This adds an llseek= method to all file operations,
// as a preparation for making no_llseek the default.
//
// The rules are
// - use no_llseek explicitly if we do nonseekable_open
// - use seq_lseek for sequential files
// - use default_llseek if we know we access f_pos
// - use noop_llseek if we know we don't access f_pos,
//   but we still want to allow users to call lseek
//
@ open1 exists @
identifier nested_open;
@@
nested_open(...)
{
<+...
nonseekable_open(...)
...+>
}

@ open exists@
identifier open_f;
identifier i, f;
identifier open1.nested_open;
@@
int open_f(struct inode *i, struct file *f)
{
<+...
(
nonseekable_open(...)
|
nested_open(...)
)
...+>
}

@ read disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
<+...
(
   *off = E
|
   *off += E
|
   func(..., off, ...)
|
   E = *off
)
...+>
}

@ read_no_fpos disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
... when != off
}

@ write @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
<+...
(
  *off = E
|
  *off += E
|
  func(..., off, ...)
|
  E = *off
)
...+>
}

@ write_no_fpos @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
... when != off
}

@ fops0 @
identifier fops;
@@
struct file_operations fops = {
 ...
};

@ has_llseek depends on fops0 @
identifier fops0.fops;
identifier llseek_f;
@@
struct file_operations fops = {
...
 .llseek = llseek_f,
...
};

@ has_read depends on fops0 @
identifier fops0.fops;
identifier read_f;
@@
struct file_operations fops = {
...
 .read = read_f,
...
};

@ has_write depends on fops0 @
identifier fops0.fops;
identifier write_f;
@@
struct file_operations fops = {
...
 .write = write_f,
...
};

@ has_open depends on fops0 @
identifier fops0.fops;
identifier open_f;
@@
struct file_operations fops = {
...
 .open = open_f,
...
};

// use no_llseek if we call nonseekable_open
////////////////////////////////////////////
@ nonseekable1 depends on !has_llseek && has_open @
identifier fops0.fops;
identifier nso ~= "nonseekable_open";
@@
struct file_operations fops = {
...  .open = nso, ...
+.llseek = no_llseek, /* nonseekable */
};

@ nonseekable2 depends on !has_llseek @
identifier fops0.fops;
identifier open.open_f;
@@
struct file_operations fops = {
...  .open = open_f, ...
+.llseek = no_llseek, /* open uses nonseekable */
};

// use seq_lseek for sequential files
/////////////////////////////////////
@ seq depends on !has_llseek @
identifier fops0.fops;
identifier sr ~= "seq_read";
@@
struct file_operations fops = {
...  .read = sr, ...
+.llseek = seq_lseek, /* we have seq_read */
};

// use default_llseek if there is a readdir
///////////////////////////////////////////
@ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier readdir_e;
@@
// any other fop is used that changes pos
struct file_operations fops = {
... .readdir = readdir_e, ...
+.llseek = default_llseek, /* readdir is present */
};

// use default_llseek if at least one of read/write touches f_pos
/////////////////////////////////////////////////////////////////
@ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read.read_f;
@@
// read fops use offset
struct file_operations fops = {
... .read = read_f, ...
+.llseek = default_llseek, /* read accesses f_pos */
};

@ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write.write_f;
@@
// write fops use offset
struct file_operations fops = {
... .write = write_f, ...
+	.llseek = default_llseek, /* write accesses f_pos */
};

// Use noop_llseek if neither read nor write accesses f_pos
///////////////////////////////////////////////////////////

@ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
identifier write_no_fpos.write_f;
@@
// write fops use offset
struct file_operations fops = {
...
 .write = write_f,
 .read = read_f,
...
+.llseek = noop_llseek, /* read and write both use no f_pos */
};

@ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write_no_fpos.write_f;
@@
struct file_operations fops = {
... .write = write_f, ...
+.llseek = noop_llseek, /* write uses no f_pos */
};

@ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
@@
struct file_operations fops = {
... .read = read_f, ...
+.llseek = noop_llseek, /* read uses no f_pos */
};

@ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
@@
struct file_operations fops = {
...
+.llseek = noop_llseek, /* no read or write fn */
};
===== End semantic patch =====

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Julia Lawall <julia@diku.dk>
Cc: Christoph Hellwig <hch@infradead.org>
2010-10-15 15:53:27 +02:00
Stefan Richter
66fa12c571 ieee1394: remove the old IEEE 1394 driver stack
The drivers
  - ohci1394 (controller driver)
  - ieee1394 (core)
  - dv1394, raw1394, video1394 (userspace ABI)
  - eth1394, sbp2 (protocol drivers)
are replaced by
  - firewire-ohci (controller driver)
  - firewire-core (core and userspace ABI)
  - firewire-net, firewire-sbp2 (protocol drivers)
which are more featureful, better performing, and more secure than the older
drivers; all with a smaller and more modern code base.

The driver firedtv in drivers/media/dvb/firewire/ contains backends to both
ieee1394 and firewire-core.  Its ieee1394 backend code can be removed in an
independent commit; firedtv as-is builds and works fine without ieee1394.

The driver pcilynx (an incomplete controller driver) is deleted without
replacement since PCILynx cards are extremely rare.  Owners of these cards
use them with the stand-alone bus sniffer driver nosy instead.

The drivers nosy and init_ohci1394_dma which do not interact with either of
the two IEEE 1394 stacks are not affected by the ieee1394 subsystem removal.

There are still some issues with the newer firewire subsystem compared to
the older one:
  - The rare and quirky controllers ALi M52xx, Apple UniNorth v1, NVIDIA
    NForce2 are even less well supported by firewire-ohci than by ohci1394.
    I am looking into the M52xx issue.
  - The experimental firewire-net is reportedly less stable than its
    experimental cousin eth1394.
  - Audio playback of a certain group of audio devices (ones based on DICE
    chipset with EAP; supported by prerelease FFADO code) does not work yet.
    This issue is still under investigation.
  - There were some ieee1394 based out-of-the-mainline drivers.  Of them,
    only lisight, an audio driver for iSight webcams, seems still useful.
    Work is underway to reimplement it on top of firewire-core.

All these remainig issues are minor; they should not stand in the way of
overall better user experience of IEEE 1394 on Linux, together with a
reduction in support efforts and maintenance burden.  The coexistence of two
IEEE 1394 kernel driver stacks in the mainline since 2.6.22 shall end now,
as announced earlier this year.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-10-11 14:48:03 +02:00
Stefan Richter
1ef5b816c0 ieee1394: move init_ohci1394_dma to drivers/firewire/
because drivers/ieee1394/ will be deleted.

Additional changes:
  - add some #include directives
  - adjust to use firewire/ohci.h instead of ieee1394/ohci1394.h,
    replace struct ti_ohci by a minimal struct ohci,
    replace quadlet_t from ieee1394_types.h by u32
  - two or three trivial stylistic changes
  - __iomem annotation

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-10-11 14:48:03 +02:00
David S. Miller
69259abb64 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	drivers/net/pcmcia/pcnet_cs.c
	net/caif/caif_socket.c
2010-10-06 19:39:31 -07:00
David S. Miller
e548833df8 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	net/mac80211/main.c
2010-09-09 22:27:33 -07:00
Heikki Lindholm
970f4be85a firewire: ohci: activate cycle timer register quirk on Ricoh chips
The Ricoh FireWire controllers appear to have the non-atomic cycle
timer register access bug, so, activate the driver workaround by
default.

The behaviour was observed on:
Ricoh Co Ltd R5C552 IEEE 1394 Controller [1180:0552] and
Ricoh Co Ltd R5C832 IEEE 1394 Controller [1180:0832] (rev 04).

Signed-off-by: Heikki Lindholm <holin@iki.fi>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-09-08 21:25:55 +02:00
Stefan Richter
a4dc090b6c firewire: ohci: work around VIA and NEC PHY packet reception bug
VIA VT6306, VIA VT6308, and NEC OrangeLink controllers do not write
packet event codes for received PHY packets (or perhaps write
evt_no_status, hard to tell).  Work around it by overwriting the
packet's ACK by ack_complete, so that upper layers that listen to PHY
packet reception get to see these packets.

(Also tested:  TI TSB82AA2, TI TSB43AB22/A, TI XIO2213A, Agere FW643,
JMicron JMB381 --- these do not exhibit this bug.)

Clemens proposed a quirks flag for that, IOW whitelist known misbehaving
controllers for this workaround.  Though to me it seems harmless enough
to enable for all controllers.

The log_ar_at_event() debug log will continue to show the original
status from the DMA unit.

Reported-by: Clemens Ladisch <clemens@ladisch.de> (VT6308)
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-08-29 09:17:31 +02:00
Clemens Ladisch
2222bcb767 firewire: core: do not use del_timer_sync() in interrupt context
Because we might be in interrupt context, replace del_timer_sync() with
del_timer().  If the timer is already running, we know that it will
clean up the transaction, so we do not need to do any further processing
in the normal transaction handler.

Many thanks to Yong Zhang for diagnosing this.

Reported-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-08-19 20:28:25 +02:00
Stefan Richter
1bf145fed5 firewire: net: fix unicast reception RCODE in failure paths
The incoming request hander fwnet_receive_packet() expects subsequent
datagram handling code to return non-zero on errors.  However, almost
none of the failure paths did so.  Fix them all.

(This error reporting is used to send and RCODE_CONFLICT_ERROR to the
sender node in such failure cases.  Two modes of failure exist:  Out of
memory, or firewire-net is unaware of any peer node to which a fragment
or an ARP packet belongs.  However, it is unclear whether a sender can
actually make use of such information.  A Linux peer apparently can't.
Maybe it should all be simplified to void functions.)

Reported-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-08-19 20:28:25 +02:00
Stefan Richter
a481e97d3c firewire: sbp2: fix stall with "Unsolicited response"
Fix I/O stalls with some 4-bay RAID enclosures which are based on
OXUF936QSE:
  - Onnto dataTale RSM4QO, old firmware (not anymore with current
    firmware),
  - inXtron Hydra Super-S LCM, old as well as current firmware
when used in RAID-5 mode, perhaps also in other RAID modes.

The stalls happen during heavy or moderate disk traffic in periods that
are a multiple of 5 minutes, roughly twice per hour.  They are caused
by the target responding too late to an ORB_Pointer register write:
The target responds after Split_Timeout, hence firewire-core cancels
the transaction, and firewire-sbp2 fails the SCSI request.  The SCSI
core retries the request, that fails again (and again), hence SCSI core
calls firewire-sbp2's abort handler (and even the Management_Agent
register write in the abort handler has the transaction timeout
problem).

During all that, the process which issued the I/O is stalled in I/O
wait state.

Meanwhile, the target actually acts on the first failed SCSI request:
It responds to the ORB_Pointer write later (seen in the kernel log as
"firewire_core: Unsolicited response") and also finishes the SCSI
request with proper status (seen in the kernel log as "firewire_sbp2:
status write for unknown orb").

So let's just ignore RCODE_CANCELLED in the transaction callback and
wait for the target to complete the ORB nevertheless.  This requires
a small modification is sbp2_cancel_orbs(); it now needs to call
orb->callback() regardless whether fw_cancel_transaction() found the
transaction unfinished or finished.

A different solution is to increase Split_Timeout on the local node.
(Tested: 2000ms timeout; maybe 1000ms or something like that works too.
200ms is insufficient.  Standard is 100ms.)  However, I rather not do
this because any software on any node could change the Split_Timeout to
something unsuitable.  Or such a large Split_Timeout may be undesirable
for other purposes.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-08-19 20:28:25 +02:00
Stefan Richter
6c74340bce firewire: sbp2: fix memory leak in sbp2_cancel_orbs or at send error
When an ORB was canceled (Command ORB i.e. SCSI request timed out, or
Management ORB timed out), or there was a send error in the initial
transaction, we missed to drop one of the ORB's references and thus
leaked memory.

Background:
In total, we hold 3 references to each Operation Request Block:
  - 1 during sbp2_scsi_queuecommand() or sbp2_send_management_orb()
    respectively,
  - 1 for the duration of the write transaction to the ORB_Pointer or
    Management_Agent register of the target,
  - 1 for as long as the ORB stays within the lu->orb_list, until
    the ORB is unlinked from the list and the orb->callback was
    executed.

The latter one of these 3 references is finished
  - normally by sbp2_status_write() when the target wrote status
    for a pending ORB,
  - or by sbp2_cancel_orbs() in case of an ORB time-out,
  - or by complete_transaction() in case of a send error.
Of them, the latter two lacked the kref_put.

Add the missing kref_put()s.  Add comments to the gets and puts of
references for transaction callbacks and ORB callbacks so that it is
easier to see what is supposed to happen.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-08-19 20:28:25 +02:00
Ben Hutchings
0141480205 ethtool: Provide a default implementation of ethtool_ops::get_drvinfo
The driver name and bus address for a net_device can normally be found
through the driver model now.  Instead of requiring drivers to provide
this information redundantly through the ethtool_ops::get_drvinfo
operation, use the driver model to do so if the driver does not define
the operation.  Since ETHTOOL_GDRVINFO no longer requires the driver
to implement any operations, do not require net_device::ethtool_ops to
be set either.

Remove implementations of get_drvinfo and ethtool_ops that provide
only this information.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-08-17 02:31:15 -07:00
Stefan Richter
e78483c5ae Merge firewire branches to be released post v2.6.35
Conflicts:
	drivers/firewire/core-card.c
	drivers/firewire/core-cdev.c

and forgotten #include <linux/time.h> in drivers/firewire/ohci.c

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-08-02 10:09:04 +02:00
Stefan Richter
2080222429 firewire: core: add forgotten dummy driver methods, remove unused ones
There is an at least theoretic race condition in which .start_iso etc.
could still be called between when the dummy driver is bound to the card
and when the children devices are being shut down.  Add dummy_start_iso
and friends.

On the other hand, .enable, .set_config_rom, .read_csr, write_csr do not
need to be implemented by the dummy driver, as commented.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-08-02 08:59:52 +02:00
Stefan Richter
872e330e38 firewire: add isochronous multichannel reception
This adds the DMA context programming and userspace ABI for multichannel
reception, i.e. for listening on multiple channel numbers by means of a
single DMA context.

The use case is reception of more streams than there are IR DMA units
offered by the link layer.  This is already implemented by the older
ohci1394 + ieee1394 + raw1394 stack.  And as discussed recently on
linux1394-devel, this feature is occasionally used in practice.

The big drawbacks of this mode are that buffer layout and interrupt
generation necessarily differ from single-channel reception:  Headers
and trailers are not stripped from packets, packets are not aligned with
buffer chunks, interrupts are per buffer chunk, not per packet.

These drawbacks also cause a rather hefty code footprint to support this
rarely used OHCI-1394 feature.  (367 lines added, among them 94 lines of
added userspace ABI documentation.)

This implementation enforces that a multichannel reception context may
only listen to channels to which no single-channel context on the same
link layer is presently listening to.  OHCI-1394 would allow to overlay
single-channel contexts by the multi-channel context, but this would be
a departure from the present first-come-first-served policy of IR
context creation.

The implementation is heavily based on an earlier one by Jay Fenlason.
Thanks Jay.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-29 23:09:18 +02:00
Stefan Richter
ae2a976614 firewire: core: small clarifications in core-cdev
Make a note on the seemingly unused linux/sched.h.
Rename an irritatingly named variable.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-29 23:09:18 +02:00
Stefan Richter
69e61d0c07 firewire: core: remove unused code
ioctl_create_iso_context enforces ctx->header_size >= 4.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-29 23:06:25 +02:00
Stefan Richter
e5b06c077c firewire: ohci: release channel in error path
firewire-ohci keeps book of which isochronous channels are occupied by
IR DMA contexts, so that there cannot be more than one context listening
to a certain channel.

If IR context creation failed due to an out-of-memory condition, this
bookkeeping leaked a channel.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-29 23:06:25 +02:00
Stefan Richter
071595ebdc firewire: ohci: use memory barriers to order descriptor updates
When we append to a DMA program, we need to ensure that the order in
which initialization of the new descriptors and update of the
branch_address of the old tail descriptor, as seen by the PCI device,
happen as intended.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-29 23:06:25 +02:00
Stefan Richter
9f6d3c4b76 tools/firewire: add userspace front-end of nosy
This adds nosy-dump, the userspace part of nosy, the IEEE 1394 traffic
sniffer for Texas Instruments PCILynx/ PCILynx2 based cards.  Author is
Kristian Høgsberg.

The files added here are taken from
git://anongit.freedesktop.org/~krh/nosy commit ee29be97 (2009-11-10)
with the following changes by Stefan Richter:
  - Parts pertaining to the kernel module removed from Makefile.
  - dist target removed from the Makefile.
  - Mentioned nosy-dump in the Kconfig help to nosy's kernel component.
  - Add copyright notice to nosy-dump.c.  This is a duplicate of the
    respective notice in the kernel component nosy.c except for a time
    span of 2002 - 2006, according to Kristian's git log.

"git shortlog decode-fcp.c list.h nosy-dump.[ch]" from nosy's git
repository:

Jonathan Woithe (1):
      Save logs on Ctrl-C

Kristian Høgsberg (11):
      Pull over nosy from mercurial repo.
      Remove some fields from default view, add logging feature.
      Use infinite time out for poll(), mark more detail fields.
      Fix byte ordering macro.
      Add decoding of iso data and lock packets.
      Add flag to indicate data length field.
      Add cycle start packet decoding, add --iso and --cycle-start flags.
      Distinguish between phy-packets and 0-length iso data.
      Fix transaction and stats view.
      Add simple AV/C decoder.
      Don't break down on big payloads.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Acked-by: Kristian Høgsberg <krh@bitplanet.net>
2010-07-27 11:04:11 +02:00
Stefan Richter
7429b17d30 firewire: nosy: use generic printk macros
Replace home-grown printk wrapper macros by ones from kernel.h and
device.h.

Also raise the log level in set_phy_reg() from debug to error because
these are really error conditions.  Could even be WARN_ON.  Lower the
log level in the device probe and driver shutdown from notice to info.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-27 11:04:11 +02:00
Stefan Richter
fd8c8d46ca firewire: nosy: endianess fixes and annotations
1.)  The DMA programs (struct pcl) are PCI-endian = little endian data
(except for the 3rd quadlet in a PCL which the controller does not
touch).  Annotate them as such.

Fix all accesses of the PCL to work with big endian CPUs also.  Not
actually tested, I only have a little endian PC to test with.  This
includes replacement of a bitfield struct pcl_status by open-coded
shift and mask operations.

2.)  The two __attribute__ ((packed)) at struct pcl are not really
required since it consists of u32/__le32 only, i.e. there will be no
padding with or without the attribute.

3.)  The received IEEE 1394 data are byteswapped by the controller from
IEEE 1394 endian = big endian to PCI endian = little endian because the
PCL_BIGENDIAN control bit is set.  Therefore annotate the DMA buffer as
a __le32 array.

Fix the one access of the DMA buffer (the check of the transaction code
of link packets) to work with big endian CPUs.  Also fix the two
accesses of the client bounce buffer (the reading of packet length).

4.)  Add a comment to the userspace ABI header that all of the data gets
out as little endian data, except for the timestamp which is CPU endian.
(We could make it little endian too, but why?  Vice versa, an ioctl
could be added to dump packet data in big endian byte order...)

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-27 11:04:11 +02:00
Stefan Richter
c89db7b8bc firewire: nosy: annotate __user pointers and __iomem pointers
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-27 11:04:11 +02:00
Stefan Richter
424d66ceda firewire: nosy: fix device shutdown with active client
Fix race between nosy_open() and remove_card() by replacing the
unprotected array of card pointers by a mutex-protected list of cards.

Make card instances reference-counted and let each client hold a
reference.

Notify clients about card removal via POLLHUP in poll()'s events
bitmap; also let read() fail with errno=ENODEV if the card was removed
and everything in the buffer was read.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-27 11:04:11 +02:00
Stefan Richter
b6d9c125e6 firewire: nosy: handle errors in device probe
and add a missing pci_disable_device() to device shutdown.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-27 11:04:10 +02:00
Stefan Richter
165476671f firewire: nosy: fix IRQ handler for card ejection
Untested, I don't have a PCILynx CardBus card.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-27 11:04:10 +02:00
Stefan Richter
55e77c06c6 firewire: nosy: unroll some simple functions
nosy_start/stop_snoop() and nosy_add/remove_client() are simple enough
to be inlined into their callers.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-27 11:04:10 +02:00
Stefan Richter
685c3f80b6 firewire: nosy: use flagless variants of spinlock accessors
nosy_start/stop_snoop() are always only called by the ioctl method, i.e.
with IRQs enabled.  packet_handler() and bus_reset_handler() are always
only called by the IRQ handler.  Hence neither one needs to track IRQ
flags.

To underline the call context of packet_handler() and
bus_reset_handler(), rename these functions to *_irq_handler().

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-27 11:04:10 +02:00
Stefan Richter
a2d39db9de firewire: nosy: fix list corruption by NOSY_IOC_STOP
nosy_stop_snoop() would blow up the second time it was called without
nosy_start_snoop() in between.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-27 11:04:10 +02:00
Stefan Richter
c7b2a99c66 firewire: nosy: convert to unlocked ioctl
The required serialization of NOSY_IOC_START and NOSY_IOC_STOP is
already provided by the client_list_lock.

NOSY_IOC_FILTER does not really require serialization since accesses
to tcode_mask are atomic on any sane CPU architecture.  Nevertheless,
make it explicit that we want this to be atomic by means of
client_list_lock (which also surrounds the other tcode_mask access in
the IRQ handler).  While we are at it, change the type of tcode_mask to
u32 for consistency with the user API.

NOSY_IOC_GET_STATS does not require serialization against itself.  But
there is a bug here regarding concurrent updates of the two counters
by the IRQ handler.  Fix it by taking the client_list_lock in this ioctl
too.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-27 11:04:10 +02:00
Stefan Richter
b5e4772904 firewire: nosy: misc cleanups
Extend copyright note to 2007, c.f. Kristian's git log.

Includes:
  - replace some <asm/*.h> by <linux/*.h>
  - add required indirectly included <linux/spinlock.h>
  - order alphabetically

Coding style related changes:
  - change to utf8
  - normalize whitespace
  - normalize comment style
  - remove usages of __FUNCTION__
  - remove an unnecessary cast from void *

Const and static declarations:
  - driver_name is not const in pci_driver.name, drop const qualifier
  - driver_name can be taken from KBUILD_MODNAME
  - the global variable minors[] can and should be static
  - constify struct file_operations instance

Data types:
  - Remove unused struct member struct packet.code.  struct packet is
    only used for driver-internal bookkeeping; it does not appear on the
    wire or in DMA programs or the userspace ABI.  Hence the unused
    member .code can be removed without worries.

Preprocessor macros:
  - unroll a preprocessor macro that containd a return
  - use list_for_each_entry

Printk:
  - add missing terminating \n in some format strings

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-27 11:04:10 +02:00
Stefan Richter
286468210d firewire: new driver: nosy - IEEE 1394 traffic sniffer
This adds the traffic sniffer driver for Texas Instruments PCILynx/
PCILynx2 based cards.  The use cases for nosy are analysis of
nonstandard protocols and as an aid in development of drivers,
applications, or firmwares.

Author of the driver is Kristian Høgsberg.  Known contributers are
Jody McIntyre and Jonathan Woithe.

Nosy programs PCILynx chips to operate in promiscuous mode, which is a
feature that is not found in OHCI-1394 controllers.  Hence, only special
hardware as mentioned in the Kconfig help text is suitable for nosy.

This is only the kernelspace part of nosy.  There is a userspace
interface to it, called nosy-dump, proposed to be added into the tools/
subdirectory of the kernel sources in a subsequent change.  Kernelspace
and userspave component of nosy communicate via a 'misc' character
device file called /dev/nosy with a simple ioctl() and read() based
protocol, as described by nosy-user.h.

The files added here are taken from
git://anongit.freedesktop.org/~krh/nosy commit ee29be97 (2009-11-10)
with the following changes by Stefan Richter:
  - Kconfig and Makefile hunks are written from scratch.
  - Commented out version printk in nosy.c.
  - Included missing <linux/sched.h>, reported by Stephen Rothwell.

"git shortlog nosy{-user.h,.c,.h}" from nosy's git repository:

Jonathan Woithe (2):
      Nosy updates for recent kernels
      Fix uninitialised memory (needed for 2.6.31 kernel)

Kristian Høgsberg (5):
      Pull over nosy from mercurial repo.
      Use a misc device instead.
      Add simple AV/C decoder.
      Don't break down on big payloads.
      Set parent device for misc device.

As a low-level IEEE 1394 driver, its files are placed into
drivers/firewire/ although nosy is not part of the firewire driver
stack.

I am aware of the following literature from Texas Instruments about
PCILynx programming:
      SCPA020A - PCILynx 1394 to PCI Bus Interface TSB12LV21BPGF
                 Functional Specification
      SLLA023  - Initialization and Asynchronous Programming of the
                 TSB12LV21A 1394 Device

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Acked-by: Kristian Høgsberg <krh@bitplanet.net>
2010-07-27 11:04:10 +02:00
Stefan Richter
8e2b2b46ea firewire: cdev: improve FW_CDEV_IOC_ALLOCATE
In both the ieee1394 stack and the firewire stack, the core treats
kernelspace drivers better than userspace drivers when it comes to
CSR address range allocation:  The former may request a register to be
placed automatically at a free spot anywhere inside a specified address
range.  The latter may only request a register at a fixed offset.

Hence, userspace drivers which do not require a fixed offset potentially
need to implement a retry loop with incremented offset in each retry
until the kernel does not fail allocation with EBUSY.  This awkward
procedure is not fundamentally necessary as the core already provides a
superior allocation API to kernelspace drivers.

Therefore change the ioctl() ABI by addition of a region_end member in
the existing struct fw_cdev_allocate.  Userspace and kernelspace APIs
work the same way now.

There is a small cost to pay by clients though:  If client source code
is required to compile with older kernel headers too, then any use of
the new member fw_cdev_allocate.region_end needs to be enclosed by
#ifdef/#endif directives.  However, any client program that seriously
wants to use address range allocations will require a kernel of cdev ABI
version >= 4 at runtime and a linux/firewire-cdev.h header of >= 4
anyway.  This is because v4 brings FW_CDEV_EVENT_REQUEST2.  The only
client program in which build-time compatibility with struct
fw_cdev_allocate as found in older kernel headers makes sense is
libraw1394.

(libraw1394 uses the older broken FW_CDEV_EVENT_REQUEST to implement a
makeshift, incorrect transaction responder that does at least work
somewhat in many simple scenarios, relying on guesswork by libraw1394
and by libraw1394 based applications.  Plus, address range allocation
and transaction responder is only one of many features that libraw1394
needs to provide, and these other features need to work with kernel and
kernel-headers as old as possible.  Any new linux/firewire-cdev.h based
client that implements a transaction responder should never attempt to
do it like libraw1394;  instead it should make a header and kernel of v4
or later a hard requirement.)

While we are at it, update the struct fw_cdev_allocate documentation to
better reflect the recent fw_cdev_event_request2 ABI addition.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-23 13:36:28 +02:00
Stefan Richter
0c9ae701ae firewire: core: fix upper bound of possible CSR allocations
region->end is defined as an upper bound of the requested address range,
exclusive --- i.e. as an address outside of the range in which the
requested CSR is to be placed.

Hence 0x0001,0000,0000,0000 is the biggest valid region->end, not
0x0000,ffff,ffff,fffc like the current check asserted.

For simplicity, the fix drops the region->end & 3 test because there is
no actual problem with these bits set in region->end.  The allocated
address range will be quadlet aligned and of a size of multiple quadlets
due to the checks for region->start & 3 and handler->length & 3 alone.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-23 13:36:28 +02:00
Stefan Richter
cc550216ae firewire: cdev: add PHY pinging
This extends the FW_CDEV_IOC_SEND_PHY_PACKET ioctl() for /dev/fw* to be
useful for ping time measurements.  One application for it would be gap
count optimization in userspace that is based on ping times rather than
hop count.  (The latter is implemented in firewire-core itself but is
not applicable to beta PHYs that act as repeater.)

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-23 13:36:28 +02:00
Stefan Richter
bf54e1462b firewire: cdev: add PHY packet reception
Add an FW_CDEV_IOC_RECEIVE_PHY_PACKETS ioctl() and
FW_CDEV_EVENT_PHY_PACKET_RECEIVED poll()/read() event for /dev/fw*.
This can be used to get information from remote PHYs by remote access
PHY packets.

This is also the 2nd half of the functionality (the receive part) to
support a userspace implementation of a VersaPHY transaction layer.

Safety considerations:

  - PHY packets are generally broadcasts, hence some kind of elevated
    privileges should be required of a process to be able to listen in
    on PHY packets.  This implementation assumes that a process that is
    allowed to open the /dev/fw* of a local node does have this
    privilege.

    There was an inconclusive discussion about introducing POSIX
    capabilities as a means to check for user privileges for these
    kinds of operations.

Other limitations:

  - PHY packet reception may be switched on by ioctl() but cannot be
    switched off again.  It would be trivial to provide an off switch,
    but this is not worth the code.  The client should simply close()
    the fd then, or just ignore further events.

  - For sake of simplicity of API and kernel-side implementation, no
    filter per packet content is provided.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-23 13:36:28 +02:00
Stefan Richter
850bb6f23b firewire: cdev: add PHY packet transmission
Add an FW_CDEV_IOC_SEND_PHY_PACKET ioctl() for /dev/fw* which can be
used to implement bus management related functionality in userspace.

This is also half of the functionality (the transmit part) that is
needed to support a userspace implementation of a VersaPHY transaction
layer.

Safety considerations:

  - PHY packets are generally broadcasts and may have interesting
    effects on PHYs and the bus, e.g. make asynchronous arbitration
    impossible due to too low gap count.  Hence some kind of elevated
    privileges should be required of a process to be able to send
    PHY packets.  This implementation assumes that a process that is
    allowed to open the /dev/fw* of a local node does have this
    privilege.

    There was an inconclusive discussion about introducing POSIX
    capabilities as a means to check for user privileges for these
    kinds of operations.

  - The kernel does not check integrity of the supplied packet data.
    That would be far too much code, considering the many kinds of
    PHY packets.  A process which got the privilege to send these
    packets is trusted to do it correctly.

Just like with the other "send packet" ioctls, a non-blocking API is
chosen; i.e. the ioctl may return even before AT DMA started.  After
transmission, an event for poll()/read() is enqueued.  Most users are
going to need a blocking API, but a blocking userspace wrapper is easy
to implement, and the second of the two existing libraw1394 calls
raw1394_phy_packet_write() and raw1394_start_phy_packet_write() can be
better supported that way.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-23 13:36:28 +02:00
Stefan Richter
b9dc61cf40 firewire: core: use C99 initializer in array of ioctl handlers
to make the correspondence of ioctl numbers and handlers more obvious.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-23 13:36:28 +02:00
Stefan Richter
18d0cdfd1a firewire: normalize status values in packet callbacks
core-transaction.c transmit_complete_callback() and close_transaction()
expect packet callback status to be an ACK or RCODE, and ACKs get
translated to RCODEs for transaction callbacks.

An old comment on the packet callback API (been there from the initial
submission of the stack) and the dummy_driver implementation of
send_request/send_response deviated from this as they also included
-ERRNO in the range of status values.

Let's narrow status values down to ACK and RCODE to prevent surprises.
RCODE_CANCELLED is chosen as the dummy_driver's RCODE as its meaning of
"transaction timed out" comes closest to what happens when a transaction
coincides with card removal.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-23 13:36:27 +02:00
Stefan Richter
02d37bed18 firewire: core: integrate software-forced bus resets with bus management
Bus resets which are triggered
  - by the kernel drivers after updates of the local nodes' config ROM,
  - by userspace software via ioctl
shall be deferred until after >=2 seconds after the last bus reset.

If multiple modifications of the local nodes' config ROM happen in a row,
only a single bus reset should happen after them.

When the local node's link goes from inactive to active or vice versa,
and at the two occasions of bus resets mentioned above --- and if the
current gap count differs from 63 --- the bus reset should be preceded
by a PHY configuration packet that reaffirms the gap count.  Otherwise a
bus manager would have to reset the bus again right after that.

This is necessary to promote bus stability, e.g. leave grace periods for
allocations and reallocations of isochronous channels and bandwidth,
SBP-2 reconnections etc.; see IEEE 1394 clause 8.2.1.

This change implements all of the above by moving bus reset initiation
into a delayed work (except for bus resets which are triggered by the
bus manager workqueue job and are performed there immediately).  It
comes with a necessary addition to the card driver methods that allows
to get the current gap count from PHY registers.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-13 09:58:27 +02:00
Stefan Richter
8b4f70ba49 firewire: cdev: fix fw_cdev_event_bus_reset emission after local config ROM changes
When a descriptor was added or removed to the local node's config ROM,
userspace clients which had a local node's /dev/fw* open did not receive
any fw_cdev_event_bus_reset for poll()/read() consumption.

The cause was that the core-device.c facility which re-reads the config
ROM of the bus reset initiator node missed to call the fw_device update
function.  The fw_units are destroyed and newly added, but their parent
stays and needs to be updated.

Reported-by: Jay Fenlason <fenlason@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-13 09:47:47 +02:00
Stefan Richter
eb5b35a560 firewire: core: ensure some userspace API constants match corresponding kernel API constants
The FW_ISO_ constants of the in-kernel API of firewire-core and
FW_CDEV_ISO_ constants of the userspace API of firewire-core have
nothing to do with each other --- except that the core-cdev.c
implementation relies on them having the same values.

Hence put some compile-time assertions into core-cdev.c.  It's lame but
I prefer it over including the userspace API header into the kernelspace
API header and defining kernelspace API constants from userspace API
constants.  Nor do I want to expose the kernelspace constants in one of
the two firewire headers that are exported to userland since this only
concerns the core-cdev.c implementation.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-13 09:47:47 +02:00
Stefan Richter
656b7afd40 firewire: core: fix fw_send_request kerneldoc comment
The present inline documentation of the fw_send_request() in-kernel API
refers to userland code that is not applicable to kernel drivers at all.

Reported-by: Ben Gamari <bgamari.foss@gmail.com>

While we are at fixing the whole documentation of fw_send_request(),
also improve the rest of firewire-core's kerneldoc comments:
  - Add a bit of text concerning fw_run_transaction()'s call parameters.
  - Append () to function names and tab-align parameter descriptions as
    suggested by the example in Documentation/kernel-doc-nano-HOWTO.txt.
  - Remove kerneldoc markers from comments on static functions.
  - Remove outdated parameter descriptions at build_tree().

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-13 09:47:47 +02:00
Clemens Ladisch
a8e93f3dcc firewire: cdev: check write quadlet request length to avoid buffer overflow
Check that the data length of a write quadlet request actually is large
enough for a quadlet.  Otherwise, fw_fill_request could access the four
bytes after the end of the outbound_transaction_event structure.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>

Modification of Clemens' change:  Consolidate the check into
init_request() which is used by the affected ioctl_send_request() and
ioctl_send_broadcast_request() and the unaffected
ioctl_send_stream_packet(), to save a few lines of code.

Note, since struct outbound_transaction_event *e is slab-allocated, such
an out-of-bounds access won't hit unallocated memory but may result in a
(virtually impossible to exploit) information disclosure.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-13 09:47:47 +02:00
Stefan Richter
250b2b6dd4 firewire: cdev: fix fw_cdev_event_bus_reset.bm_node_id
Fix an obscure ABI feature that is a bit of a hassle to implement.
However, somebody put it into the ABI, so let's fill in a sensible
value there.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-08 16:52:02 +02:00
Stefan Richter
ae94801107 firewire: core: no need to track irq flags in bm_work
This is a workqueue job and always entered with IRQs enabled.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-08 16:45:54 +02:00
Stefan Richter
e205597d18 firewire: cdev: fix ABI for FCP and address range mapping, add fw_cdev_event_request2
The problem:

A target-like userspace driver, e.g. AV/C target or SBP-2/3 target,
needs to be able to act as responder and requester.  In the latter role,
it needs to send requests to nods from which it received requests.  This
is currently impossible because fw_cdev_event_request lacks information
about sender node ID.
Reported-by: Jay Fenlason <fenlason@redhat.com>

Libffado + libraw1394 + firewire-core is currently unable to drive two
or more audio devices on the same bus.
Reported-by: Arnold Krille <arnold@arnoldarts.de>

This is because libffado requires destination node ID of FCP requests
and sender node ID of FCP responses to match.  It even prohibits
libffado from working with a bus on which libraw1394 opens a /dev/fw* as
default ioctl device that does not correspond with the audio device.
This is because libraw1394 does not receive the sender node ID from the
kernel.

Moreover, fw_cdev_event_request makes it impossible to tell unicast and
broadcast write requests apart.

The fix:

Add a replacement of struct fw_cdev_event_request request, boringly
called struct fw_cdev_event_request2.  The new event will be sent to a
userspace client instead of the old one if the client claims
compatibility with <linux/firewire-cdev.h> ABI version 4 or later.

libraw1394 needs to be extended to make use of the new event, in order
to properly support libffado and other FCP or address range mapping
users who require correct sender node IDs.

Further notes:

While we are at it, change back the range of possible values of
fw_cdev_event_request.tcode to 0x0...0xb like in ABI version <= 3.
The preceding change "firewire: expose extended tcode of incoming lock
requests to (userspace) drivers" expanded it to 0x0...0x17 which could
catch sloppily coded clients by surprise.  The extended range of codes
is only used in the new fw_cdev_event_request2.tcode.

Jay and I also suggested an alternative approach to fix the ABI for
incoming requests:  Add an FW_CDEV_IOC_GET_REQUEST_INFO ioctl which can
be called after reception of an fw_cdev_event_request, before issuing of
the closing FW_CDEV_IOC_SEND_RESPONSE ioctl.  The new ioctl would reveal
the vital information about a request that fw_cdev_event_request lacks.
Jay showed an implementation of this approach.

The former event approach adds 27 LOC of rather trivial code to
core-cdev.c, the ioctl approach 34 LOC, some of which is nontrivial.
The ioctl approach would certainly also add more LOC to userspace
programs which require the expanded information on inbound requests.
This approach is probably only on the lighter-weight side in case of
clients that want to be compatible with kernels that lack the new
capability, like libraw1394.  However, the code to be added to such
libraw1394-like clients in case of the event approach is a straight-
forward additional switch () case in its event handler.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-20 23:11:56 +02:00
Jay Fenlason
c82f91f266 firewire: expose extended tcode of incoming lock requests to (userspace) drivers
When a remote device does a LOCK_REQUEST, the core does not pass
the extended tcode to userspace.  This patch makes it use the
juju-specific tcodes listed in firewire-constants.h for incoming
requests.

Signed-off-by: Jay Fenlason <fenlason@redhat.com>

This matches how tcode in the API for outbound requests is treated.
Affects kernelspace and userspace drivers alike, but at the moment there
are no kernespace drivers that receive lock requests.

Split out from a combo patch, slightly reordered, changelog reworded.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-20 23:11:56 +02:00
Stefan Richter
604f451678 firewire: cdev: freeze FW_CDEV_VERSION due to libraw1394 bug
libraw1394 v2.0.0...v2.0.5 takes FW_CDEV_VERSION from an externally
installed header file and uses it to declare its own implementation
level in FW_CDEV_IOC_GET_INFO.  This is wrong; it should set the real
version for which it was actually written.

If we add features to the kernel ABI that require the kernel to check
a client's implementation level, we can not trust the client version if
it was set from FW_CDEV_VERSION.

Hence freeze FW_CDEV_VERSION at the current value (no damage has been
done yet), clearly document FW_CDEV_VERSION as a dummy version and what
clients are expected to do with fw_cdev_get_info.version, and use a new
defined constant (which is not placed into the exported header file) as
kernel implementation level.

Note, in order to check in client program source code which features are
present in an externally installed linux/firewire-cdev.h, use
preprocessor directives like
  #ifdef FW_CDEV_IOC_ALLOCATE_ISO_RESOURCE
or
  #ifdef FW_CDEV_EVENT_ISO_RESOURCE_ALLOCATED
instead of a check of FW_CDEV_VERSION.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-20 23:11:56 +02:00
Stefan Richter
0244f57302 firewire: cdev: count references of cards during inbound transactions
If a request comes in to an address range managed by a userspace driver
i.e. <linux/firewire-cdev.h> client, the card instance of request and
response may differ from the card instance of the client device.
Therefore we need to take a reference of the card until the response was
sent.

I thought about putting the reference counting into core-transaction.c,
but the various high-level drivers besides cdev clients (firewire-net,
firewire-sbp2, firedtv) use the card pointer in their fw_address_handler
address_callback method only to look up devices of which they already
hold the necessary references.  So this seems to be a specific
firewire-cdev issue which is better addressed locally.

We do not need the reference
  - in case of FCP_REQUEST or FCP_RESPONSE requests because then the
    firewire-core will send the split transaction response for us
    already in the context of the request handler,
  - if it is the same card as the client device's because we hold a
    card reference indirectly via teh client->device reference.
To keep things simple, we take the reference nevertheless.

Jay Fenlason wrote:
> there's no way for the core to tell cdev "this card is gone,
> kill any inbound transactions on it", while cdev holds the transaction
> open until userspace issues a SEND_RESPONSE ioctl, which may be a very,
> very long time.  But when it does, it calls fw_send_response(), which
> will dereference the card...
>
> So how unhappy are we about userspace potentially holding a fw_card
> open forever?

While termination of inbound transcations at card removal could be
implemented, it is IMO not worth the effort.  Currently, the effect of
holding a reference of a card that has been removed is to block the
process that called the pci_remove of the card.  This is
  - either a user process ran by root.  Root can find and kill processes
    that have /dev/fw* open, if desired.
  - a kernel thread (which one?) in case of hot removal of a PCCard or
    ExpressCard.
The latter case could be a problem indeed.  firewire-core's card
shutdown and card release should probably be improved not to block in
shutdown, just to defer freeing of memory until release.

This is not a new problem though; the same already always happens with
the client->device->card without the need of inbound transactions or
other special conditions involved, other than the client not closing the
file.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-20 23:11:56 +02:00
Jay Fenlason
08bd34c98d firewire: cdev: fix responses to nodes at different card
My box has two firewire cards in it: card0 and card1.
My application opens /dev/fw0 (card 0) and allocates an address space.
The core makes the address space available on both cards.
Along comes the remote device, which sends a READ_QUADLET_REQUEST to
card1.  The request gets passed up to my application, which calls
ioctl_send_response().

ioctl_send_response() then calls fw_send_response() with card0,
because that's the card it's bound to.
Card0's driver drops the response, because it isn't part of
a transaction that it has outstanding.

So in core-cdev: handle_request(), we need to stash the
card of the inbound request in the struct inbound_transaction_resource and
use that card to send the response to.

The hard part will be refcounting the card correctly
so it can't get deallocated while we hold a pointer to it.

Here's a trivial patch, which does not do the card refcounting, but at
least demonstrates what the problem is.

Note that we can't depend on the fact that the core-cdev:client
structure holds a card open, because in this case the card it holds
open is not the card the request came in on.

..and there's no way for the core to tell cdev "this card is gone,
kill any inbound transactions on it", while cdev holds the transaction
open until userspace issues a SEND_RESPONSE ioctl, which may be a very,
very long time.  But when it does, it calls fw_send_response(), which
will dereference the card...

So how unhappy are we about userspace potentially holding a fw_card
open forever?

Signed-off-by: Jay Fenlason <fenlason@redhat.com>

Reference counting to be addressed in a separate change.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (whitespace)
2010-06-20 23:11:56 +02:00
Clemens Ladisch
bdfe273ee5 firewire: cdev: fix race in iso context creation
Protect the client's iso context pointer against a race that can happen
when more than one creation call is executed at the same time.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-20 23:11:56 +02:00
Stefan Richter
33e553fe2b firewire: remove an unused function argument
void (*fw_address_callback_t)(..., int speed, ...) is the speed that a
remote node chose to transmit a request to us.  In case of split
transactions, firewire-core will transmit the response at that speed.

Upper layer drivers on the other hand (firewire-net, -sbp2, firedtv, and
userspace drivers) cannot do anything useful with that speed datum,
except log it for debug purposes.  But data that is merely potentially
(not even actually) used for debug purposes does not belong into the API.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-20 23:11:55 +02:00
Stefan Richter
56d04cb189 firewire: core: remove an unnecessary zero initialization
All of the fields of the iso_interrupt_event instance are overwritten
right after it was allocated.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-20 17:06:25 +02:00
Stefan Richter
ae86e81e43 firewire: core: remove unused variable
which caused gcc 4.6 to warn about
    variable 'destination' set but not used.

Since the hardware ensures that we receive only response packets with
proper destination node ID (in a given bus generation), we have no use
for destination here in the core as well as in upper layers.

(This is different with request packets.  There we pass destination node
ID to upper layers because they may for example need to check whether
this was an unicast or broadcast request.)

Reported-and-Tested-By: Justin P. Mattock <justinmattock@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-19 13:01:41 +02:00
Stefan Richter
0fcff4e393 firewire: rename CSR access driver methods
Rather than "read a Control and Status Registers (CSR) Architecture
register" I prefer to say "read a Control and Status Register".

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-19 13:01:41 +02:00
Stefan Richter
b384cf1887 firewire: core: combine some repeated code
All of these CSRs have the same read/ write/ aynthing-else handling,
except for CSR_PRIORITY_BUDGET which might not be implemented.

The CSR_CYCLE_TIME read handler implementation accepted 4-byte-sized
block write requests before this change but this is just silly; the
register is only required to support quadlet read and write requests
like the other r/w CSR core and Serial-Bus-dependent registers.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-19 13:01:41 +02:00
Stefan Richter
c8a94ded57 firewire: normalize STATE_CLEAR/SET CSR access interface
Push the maintenance of STATE_CLEAR/SET.abdicate down into the card
driver.  This way, the read/write_csr_reg driver method works uniformly
across all CSR offsets.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-19 13:01:41 +02:00
Stefan Richter
db3c9cc105 firewire: replace get_features card driver hook
by feature variables in the fw_card struct.  The hook appeared to be an
unnecessary abstraction in the card driver interface.

Cleaner would be to pass those feature flags as arguments to
fw_card_initialize() or fw_card_add(), but the FairnessControl register
is in the SCLK domain and may therefore not be accessible while Link
Power Status is off, i.e. before the card->driver->enable call from
fw_card_add().

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-19 13:01:41 +02:00
Stefan Richter
e847cc832b firewire: drop sizeof expressions from some request size arguments
In case of fw_card_bm_work()'s lock request, the present sizeof
expression is going to be wrong if somebody changes the fw_card's DMA
scratch buffer's size in the future.

In case of quadlet write requests, sizeof(u32) is just silly; it's 4.

In case of SBP-2 ORB pointer write requests, 8 is arguably quicker to
understand as the correct and only possible value than
sizeof(some_datum).

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-19 13:01:40 +02:00
Stefan Richter
65b2742ac0 firewire: 'add CSR_... support' addendum
Add a comment on which of the conflicting NODE_IDS specifications we
implement.  Reduce a comment on rather irrelevant register bits that can
all be looked up in the spec (or from now on in the code history).
Directly include the required indirectly included bug.h.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-19 13:01:40 +02:00
Clemens Ladisch
c374ab4242 firewire: core: always enable cycle master packets
As part of the bus manager responsibilities, make sure that the cycle
master sends cycle start packets.  This is needed when the old bus
manager disabled the cycle master's cmstr bit and there are iso-capable
nodes on the new bus.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:41:51 +02:00
Clemens Ladisch
e91b2787d0 firewire: allocate broadcast channel in hardware
On OHCI 1.1 controllers, let the hardware allocate the broadcast channel
automatically.  This removes a theoretical race condition directly after
a bus reset where it could be possible to read the channel allocation
register with channel 31 still being unallocated.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:40:49 +02:00
Clemens Ladisch
7e0e314f19 firewire: core: add CSR abdicate support
Implement the abdicate bit, which is required for bus manager
capable nodes and tested by the Base 1394 Test Suite.

Finally, something to do at a command reset!  :-)

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:37:15 +02:00
Clemens Ladisch
4ffb7a6a06 firewire: add CSR cmstr support
Implement the cmstr bit, which is required for cycle master capable
nodes and tested for by the Base 1394 Test Suite.

This bit allows the bus master to disable cycle start packets; there are
bus master implementations that actually do this.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:36:37 +02:00
Clemens Ladisch
3d1f46eb60 firewire: core: add CSR MAINT_UTILITY support
Implement the MAIN_UTILITY register, which is utterly optional
but useful as a safe target for diagnostic read/write/broadcast
transactions.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:35:37 +02:00
Clemens Ladisch
a1a1132bd8 firewire: add CSR PRIORITY_BUDGET support
If supported by the OHCI controller, implement the PRIORITY_BUDGET
register, which is required for nodes that can use asynchronous
priority arbitration.

To allow the core to determine what features the lowlevel device
supports, add a new card driver callback.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:35:06 +02:00
Clemens Ladisch
27a2329f82 firewire: add CSR BUSY_TIMEOUT support
Implement the BUSY_TIMEOUT register, which is required for nodes that
support retries.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:34:13 +02:00
Clemens Ladisch
a48777e03a firewire: add CSR BUS_TIME support
Implement the BUS_TIME register, which is required for cycle master
capable nodes and tested for by the Base 1393 Test Suite.  Even when
there is not yet bus master initialization support, this register allows
us to work together with other bus masters.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:33:07 +02:00
Clemens Ladisch
9ab5071cd4 firewire: add CSR CYCLE_TIME write support
The specification requires that CYCLE_TIME is writable so that it can be
initialized, so we better implement it.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:26:48 +02:00
Clemens Ladisch
8e4b50f94e firewire: core: add CSR SPLIT_TIMEOUT support
Implement the SPLIT_TIMEOUT registers.  Besides being required by the
spec, this is desirable for some IIDC devices and necessary for many
audio devices to be able to increase the timeout from userspace.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:26:28 +02:00
Clemens Ladisch
446eba0d68 firewire: core: add CSR RESET_START support
This implements the RESET_START register (as a dummy) to make the Base
1394 Test Suite happy.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:25:46 +02:00
Clemens Ladisch
506f1a3193 firewire: add CSR NODE_IDS support
The NODE_IDS register, and especially its bus_id field, is quite
useless because 1394.1 requires that the bus_id field always stays
0x3ff.  However, the 1394 specification requires this register on all
transaction capable nodes, and the Base 1394 Test Suite tests for it,
so we better implement it.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:25:19 +02:00